阅读以下程序及对程序功能的描述,其中正确的描述是 #include<stdio.h> main() { FILE*in,*out; char ch,infile[10],outfile[10]; printf('Enter the infile name:/n'); scanf('%s',infile); printf('Enter the outfile name:/n'); scanf('%s',outfile); if((in=fopen(infile,'r'))==NULL) { printf('cannot open infile/n'); exit(0);} if((out=fopen(outfile,'w'))==NULL) { printf('cannot open outfile/n'); exit(0);} while(!feof(in))fputc(fgetc(in),out); fclose(in); fclose(out);}